深夜|しんやshin'ya[1]atamadaka (head-high)

1. noun, adverblate at night
   深夜しんやテレビでカウボーイの映画えいがを見みましたか。↗

   Did you see the cowboy film on TV last night?

• Synonym夜中よなかNeutralEveryday word for the night, common in speech; 「深夜」 sounds more formal and is typical of news reports and business hours.
• Synonym真夜中まよなかNeutralThe deepest part of the night, around midnight — more vivid than 「深夜」, which covers a wider span and can also refer to the hours around midnight.
• Synonym夜半やはんWrittenWritten word for the middle of the night, found in literature and weather forecasts, as in 「夜半から雨」.
• Synonym半夜はんやNeutralMeans the middle of the night but is rarely used in Japanese; it can also refer to half of a night.
• Synonym深更しんこうWrittenWritten word for late at night, seen in set phrases such as 「深更に及ぶ」.
• Related零時れいじNeutralThe exact stroke of midnight, a single point in time; 「深夜」 refers to a period of the night.
• RelatedミッドナイトNeutralLoanword for midnight, mostly seen in song titles and product names rather than everyday speech.
• Related１２時じゅうにじNeutralSimply 'twelve o'clock'; it can mean either noon or midnight, so context must make clear which is meant.
• Related正子しょうしWrittenAstronomical term for exactly midnight (0:00); not used in everyday conversation.
• Antonym真昼まひるNeutralMidday or broad daylight — the direct opposite of 「深夜」.
• Antonym正午しょうごNeutralNoon, twelve o'clock in the day — the counterpart of the midnight hour.
• Antonym日中にっちゅうNeutralDaytime, the hours when the sun is up — the opposite of 「深夜」.

Use 「深夜」 in formal contexts like news and business hours; 「夜中」 is the everyday spoken word, and 「真夜中」 vividly points to the deepest hours around midnight. 「零時」 is the exact stroke of midnight; 「１２時」 needs context to tell noon from midnight. 「夜半」「深更」「正子」 are written or technical, 「ミッドナイト」 appears in titles and brand names, 「半夜」 is rare. Daytime: 「日中」, 「正午」 (noon), 「真昼」 (broad daylight).

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 夜更よふけ。